Among the most widely used synthetic fibers in the clothing industry are spandex and nylon yarns. Spandex is usually combined in fabrics with other types of fibers, and imparts to the fabrics elasticity. Nylon yarns are universally used for their versatility, either alone or blended with other yarns. An important yarn, especially used in hosiery, is spandex covered with nylon. The type of wrapping affects the transparency, softness, and durability of the covered spandex and the garment in which it is used. Use of such yarn is described, e.g., in U.S. Pat. No. 3,788,365 where this material was employed for making elastic waistbands. U.S. Pat. No. 5,478,514 describes a process for preparing a woven fabric of spandex and nylon, and the heat treatment of the fabric at a temperature from 80° C. to 180° C.
In the covered spandex yarn of the prior art, the nylon fiber does not tightly wrap the whole length of the spandex core, but it winds around the spandex axis rather in the form of an irregular and fuzzy coil, with loops of various sizes sticking out. These loops are undesired and are susceptible to picks and snags of filament, causing tears of the fabric during its production or in use of the garment. It is therefore an objective of this invention to provide a yarn in which spandex is wrapped with nylon yarn more tightly, resulting in reduced protrusions of nylon loops perpendicularly to spandex core.
It is another object of this invention to provide a fabric based on spandex/nylon with lowered susceptibility to picks and snags.
Other objects and advantages of present invention will appear as description proceeds.